Electrical furnace



No. 625,252. Pate nted May 16, I899.

H. ELDRIDGE, D. J. CLARK & S. BLUM. ELECTRICAL FURNACE.

(Application filed Ian. 18, 1898.) (No Model.) 2 Sheets-Sheet l.

by iil zsses Patented May l6, I899.

H. ELDRIDGE, D; J. CLARK 8|. S. BLUM. ELECTRICAL FURNACE.

(Application flied Jan. 18, 1898.)

2 Sheets-Sheat 2.

(No Model.)

UNITED STATES HILLIARY ELDRIDGE, DANIEL JOHNSON CLARK, AND SYLVAIN BLUM, OF

PATENT vOFFICE.

GALVESTON, TEXAS.

ELECTRICAL FU RNACE.

SPECIFICATION forming part of Letters Patent No. 625,252, dated May' 16,1899.

Original application filed September 29, 1897, Serial No. 653,450 Divided and this application filed J'anuary18,1893. Serial No. 667,101. (No hiodel.)

T aZZ whom, it may concern.-

Be it known that we, HILLIARY ELDRIDGE, DANIEL JOHNSON OLAEK,and SYLVAIN BLUM, citizens of the United States, residing at Galveston, in the county of Galveston and State of Texas, have invented a new and useful Electrical Furnace, of which the following is a specification.

Our invention relates to improvements in electrical furnaces or retorts, and it constitutes a division of the prior application filed by us on September 29,1897, Serial No. 653,450.

The electrical furnace which forms the subject-matter of the present application is especially designed for use in connection with an apparatus for manufacturing calcium carbid and illuminating or heating gas, substantially as disclosed in our prior application to which reference has been made; but it will be understood that we do not restrict ourselves to this specific employment of the electrical furnace or retort, because we are aware that it may be used advantageously in other arts.

One of the objects that we havein view is to provide means arranged to secure easy access to the retort-chamber for the purpose of chargingthe substance therein to be treated by the heat from the electric arci A further object is to so arrange the several working parts of the improved furnace that they may be manipulated or controlled with ease and at the same time to provide for the collection and discharge of the fumes and gases which may arise from the furnace retort or chamber during the treatment of the charge therein.

With these ends in view ourinvention consists in the combination, with an inclosed f urnace-chamber, of a vertically-adj ustable fumecollecting hood, a hanger over said hood, insulated guide-boxes carried by the hangerand thehood, andasuspended anode which passes through the said insulated guide-boxes and is adapted to coact with a cathode fixed in the bottom of the furnace-chamber.

The invention further consists in the combination, with the inclosed furnace-chamber, of a revoluble carrier mounted thereon and supporting a closure or head, a stirrer or plow mounted 011 the carrier and depending therefrom into the inclosed furnace-chamber, and suitable drivingmeans for said carrier; and the invention further consists in the novel construction and arrangement of parts which will be hereinafter fully described. and claimed.

To enable others to understand our invention, we have illustrated one embodiment thereof in the accompanying drawings, forminga-part of this specification, andin which Figure 1 is a vertical sectional elevation through the electrical furnace constructed in accordance with our invention. Fig. 2 is a detail plan view illustrating the revoluble carrier and the sectional head or closure which is mounted on said carrier. Fig. 3 isa detail sectional view on the plane indicated by the dottedline 3 3 of Fig. 1, looking in the direction indicated by the arrow. Fig. 4 is a detail fragmentary viewin plan of the plow or stirrer which is carried by the rotatable head and carrier of the furnace.

Like numerals of reference indicate like parts in all the figures of the drawings.

The electrical furnace of our invention embodies a structure 1, which is constructed of masonry or fire-brick in any suitable way to provide a chamber 2. We prefer the firebrick construction of the furnace, because it is better adapted to resist the intense heat generated by the electrical appliances of the furnace. The bottom of the chamber 2 is constructed with a cavity 3, in which is fitted a central sectional cathode 4: 4. The members of this sectional cathode are preferably made of metal, although other suitable material may be employed, if desired. The lower member of this sectional cathode is permanently fastened or seated in the cavity 3 of cathode, which is exposed to the intense heat of the electric arc, in consequence of which it is liable to deteriorate and wear out, is preferably applied to the permanent lower member in a manner to permit its removal in order that said member at may be renewed when worn.

The electrical connection between one of the conductors of the circuit and the cathode .9 the chamber; but the other member of said is effected by the employment of a metallic and 6, which passes through a suitable passage formed in the brickwork of the furnace. The inner end of this rod is screw-threaded to engage with a correspondingly-threaded opening in the members 4 4 of the cathode; but the outer end of the rod is clamped or otherwise fixed to one of the conductors 7 of the electrical circuit.

The anode 8 extends vertically through the inclosed furnace-chamber in axial relation thereto and to the cathode, and the lower end of said anode is thus adapted to be presented centrally to the removable member 4 of the cathode. The anode consists, preferably, of a pencil or rod of carbon which is fitted within a tubular carrier 9, suspended above the inclosed f urn ace-chamber by mean s which permit of the vertical adjustment of said carrier9 and the anode 8 therein for the purpose of establishing and regulating the electrical are between theanode and cathode, as required.

Over the chamberof the furnace is arranged a suspension-beam 13, which may be supported from the roof or in an overhead position by any suitable means. This suspensionbeam sustains a hood 10, the means for suspending and adjusting said hood, and the suspending devices for the anode and its tubular carrier. The hood 10 is of conical or funnel shape, substantially as represented by Fig. l of the drawings, and it is suspended over the inclosed furnace-chamber in a manner to have its broad lower open end adjacent to the inclosed furnace-chamber in order that it may entirely surround the upper partthereof and collect the fumes and gases arising 'from the inclosed furnace-chamber during the fusing of the calcium oxid and carbon necessary to produce the calcium carbid.

On. the upper edge of the wall surrounding the retort-chamber is rigidly fastened a metallic bearing-plate 11, which serves as asupport for a series of angular brackets 12, the latter being bolted rigidly. to said bearingplate, substantially as shown at the righthand side of Fig. 1. These brackets extend upwardly from the inclosed furnace chamber and have the inclined extremities 13, which form seats for the reception of the lower edge of the fume-collecting hood 10, and the upper end of said fume-collecting hood terminates in a tubular extension 15, to which is fastened a bearing-ring 16. Said bearingring is flanged to fit snugly to the tubular extension of the fume-collecting hood, and it is provided with vertical openings or sockets 17 to receive the lower extremities of the vertical guide-rods 19. The bearing-ring, the tubular extension of the fu me-collectinghood, and the guide-rods for said hood are all united solidly together by through-bolts 20, which pass through said parts, substantially as shown by Fig. 1." v

To the overhead suspension-beam is rigidly bolted the flanged upper end of a hanger 21,

which is provided above the electrical appliance of the furnace to form a means which assists .in guiding the rods of the fume-collecting hood and also as one of the guides for the tubular carrier of the anode. This hanger 21 has its lower head provided with a guide-box consisting of an upwardly-projecting sleeve 22, a bushing 23, and a gland 24. The sleeve 22 is integral with the lower head of the hanger and it is externally threaded to receive an internal thread on the gland 24. Said bushing 23 is of electrical insulating material, and it is confined within the sleeve and gland of the guide-box, so as to engage directly with the tubular carrier of the movable anode, and this bushing serves to insulate the anode and its tubular carrier electrically from the metallic parts of the guide-box, the hanger, and the other overhead devices of the electrical furnace. The upper extremity of the tubular anode-carrier protrudes above the guide-box of the hanger 21, and to said extremity of the anode-carrier is 'fas'tene'd a head 25, which is socketed to receive the conductor 7 which, in connection with the conductor 7, forms a part of the electrical circuit, said conductors being clamped in the head 25 by means of set-screws or other suitable devices. To the eye of the head 25 is connected one end of a suspension cable, rope, or chain 26,which passes upwardly over a guidesheave 27, the frame of which is bolted or otherwise fastened to the suspension-beam 13, and said suspension cable or chain 26 receives a dropweight. (Not shown.) This drop-weight serves as a counterpoise for the anode and its carrier to adapt the latter to move easily and freely and to be adjusted vertically, as may be required. The tubular carrier for the anode terminates at its lower end in an enlarged foot, having a clamping screw 9, adapted to bind upon the carbon pencil or rod which forms the anode and to clamp the latter rigidly and adjustably within said tubular carrier 9. The guide-rods for the fumecollecting hood pass through suitable apertures provided in the upper and lower ends of the hanger 21 and the overhead suspension-beam, and these rods thus serve to direct the fume-collecting hood in astraight vertical line and keep it from swaying out of position with relation to the inclosed furnace-chamber and to the angular brackets upon which the lower front end of thehood is adapted to be seated when said hood is lowered into close relation to the inclosed furnace-chamber.

The bearin g-rin g, hereinbefore described, is provided with the laterally-extendinglugs 28, to which are attached weight-carrying ropes or chains 29, that are reeved through suitable sheaves 30, whichare bolted or otherwise fastened to the suspension-beam The weighted cables 29 counterpoise the fume-collecting hood and enable the latter to be raised and lowered easily and quickly, so that access may be obtained to the chamber of the furnace. The flanged bearing-ring being at- ICO IIO.

tached rigidly to the fume-collecting hood, provision must be made for the exit of the fumes and gases therefrom, and we attain this object and also. provide a guide-box for the anode-carrier by a novel construction of the guide-box itself. This guide-box 31 is arranged centrally Within the bearing-ring to provide openings or slots 32, which constitute the exit openings or passages for the gases.

and fumes from the hood, and said box 31 has a sleeve 33 depending centrally from the bearing-ring, a gland 34, and an insulating-bushing 35. The guide-box sleeve 33 is joined to the bearing-ring by the radial webs 36, and the lower end of said sleeve 33 is threaded to receive the gland 34, which is screwed on the sleeve to confine the bushing 35 within said sleeve and in electrical contact with the anodecarrier12. This bushing 35 is of electrical insulating material, arranged to have-direct contact with the anode-carrier and to insulate the bearing-ring and the hood electrically from said anode-carrier. The'insulated guideboX is situated in the bearing-ring and on the hood in vertical alinement with the insulated guide-box on the lower end of the hanger 21, whereby said anode-carrier is adapted to pass through both insulated guide-boxes and to be guided in a straight vertical line thereby.

The bearing-plate on the upper edge of the furnace is provided in its upper surface with a groove, forming aball-race for the reception of a series of antifriction balls or rolls 3'7, and upon this ball-bearin g rests the rotatable carrier 38. (Shown by Figs. 1 and 2.) Said rotatable carrier consists of a ring or annulus occupying a horizontal position in compact relation to the upper open side of the furnace, andsaid carrier is adapted for rotation in a horizontal plane on the furnace in order to move the stirrer or plow 39 within the furnace-chamber. In one embodiment of our invention this rotatable carrier 38 is provided with a series of gear-teeth on its peripheral edge, with which teeth meshes a spur-gear pinion 40, which is fastened to the upper end of a shaft 41. This shaft is journaled at its upper end in a suitable bearing of the frame 42, situated extcriorly to the furnace, and the lowerend of said shaft is steppedin a bearing 43 on the base of said frame 42, the latter being bolted or otherwise fastened to the base or floor of the furnace. V

The rotatable oarrier38sustainsasectional head or closure 44 44, which is of substantiallydi'sk-like form and adapted when closed to lie within said ring-like carrier. The sections of the head or closure are provided with lugs or ears 45, which are hinged at 46 to diametrically opposite sides, of the carrier 38, and said sections of the closure are provided near theirinner free edges with lugs 47,adapted to rest when the sections are closed upon the carrier and limit the folding or closing movement of the sections whichform the head or closure. The pivotal connections 46 between the sectional closure and the rotatable carrier occupy positions above the horizontal plane of the carrier, as shown by Fig. 1, and thus the sections of the closure may be drawn upwardly and outwardly to occupy positions when open entirely out of the way of the f urnace-chamber. The adjacent inner edges of the hinged sections of the head or closure are recessed at 49 to provide a central opening therein for the passage of the anode and its carrier, thus permitting the .head or closure, said shank being'clamped rigidly in position by a binding-screw 39 or its equivalent.

The shaft 41 has a pulley 48 or other driving appliance for imparting rotary motion to said shaft, and the shaft is adapted, to drive the carrier 38, the sectional closure or head mounted on said carrier, and the plow or stirrer 39, so that the latter is adapted .to travel in a horizontal plane Within the 'material contained in the furnace-chamber, thus stirring up said material and feeding fresh material within the zone of the electric are between the anode and the two-part cathode 4 4.

' As disclosed by our prior application, of which the present case is a division, the furnace is provided within the closed chamber 2 thereof with two series of heating-coils, one of which is adapted for the purpose of heating air and the other series of coils receive gaseous vapors which circulate through said coils to fix the gases. These two series of coils are arranged concentric one with the other, and both series of coils surround the arc forming appliances, situated centrally within the inclosed furnace chamber. In Fig. 1 of the drawings a vertical series of airheating pipes 48 lie within the furnace-chamber 2, contiguous to the surrounding wall thereof, and within these pipes or coils 48 is another series of heating-pipes 49, which are concentric with the first-named series of pipes. The heating-pipes 48 are arranged to receive or be supplied with air from the inclosed furnace-chamber 2, and to the final pipe of the series of pipes 48'is connected an off-bearing pipe 50, which extends through the furnace and is adapted to be connected with a suitable receiver, such as a carbureter. The other series of pipes 49 has an inlet-pipe 51 connected thereto, and this inlet-pipe extends through the furnace, so as to be properly connected with a source of gas-supply, whereby the inlet-pipe 51 is adapted to convey the gaseous vapors to the series of pipes 49, so as the arc-forming appliances within the furnace-chamber the pipes are exposed to the heat generated by the electric arc-and the incandescent material which is treated within the furnace, and said pipes are thus adapted to be heated to a hi h temperature. It is evident, however, that the outer series of pipes 48 will not be heated as highly as the inner series of pipes 49, because they are outside of the pipes 49 and somewhat remote to the source of heat.

The operation of the furnace may be described briefly as follows: The anode-carrier is lowered until the anode comes in contact with the cathode in the bottom of the furnacechamber, after which the closure 44 44 is opened and the chamber is filled or charged with the mixture or substance which it is desired to treat. The cover is now closed,and the electric current is turned on through the conductors '7 7, said current passing through the anode-holder, the anode, the cathode, and the rod extending outwardly from said cathode. By lifting the anode and its carrier upwardly a suitable distance the electric arc is established between the cathode and the proximal end of the anode thereto, and the heat generated by the electric arc fuses the materials within the furnace-chamber in awelhknown manner. The carrier 88 is rotated by the shaft 41 to impart traveling movement to the plow or stirrer-in the materials contained within the inclosed furnacechamber, and as the mixture fuses under the action of the electric arc the plow or stirrer continually throws fresh mixture within the zone of the electric arc. The fumes and gases arising from the chamber of the furnace are collected by the hood and discharged from the upper end thereof. When it is desired to obtain access to the furnacechamber, it is necessary to raise the hood and open the sectional closure, thus exposing the chamber in the furnace for the removal of the treated charge and for placing therein a fresh charge of material to be treated.

Changes in the form, proportion, and the minor details of construction be resorted to without departing from the spirit or sacrificing any of the advantages of this invention.

Having thus described our invention, what we claim is- 1. In an electrical furnace, the combination with an inclosed furnace-chamber, and a cathode therein, of a vertically-adjustable hood arranged over the furnace-chamber, and a Verticallyadj ustable anode carrier, guided through and insulated from said hood, said hood and anode-carrier being adjustable independently of each other, substantially as described. I

2. In an electrical furnace, the combination with an inclosed furnace-chamber, and a cathode therein, of a counterpoised fume-collecting hood suspended over said furnace-chamber,and a counterpoised anode-carrier, guided through said hood and adjustable independently thereof with relation to the cathode, substantially as described.

3. In an electricalfurnace, the combination with an inclosed furnace-chamber. having a cathode, of a vertically-adjustable fume-collecting hood suspended over said furnacechamber, and an anode. guided through and insulated from said hood, substantially as described.

- 4. In an electrical furnace, the combination with an inclosed furnace-chamber having a cathode, of a fume-collecting hood, ahanger, insulated guide-boxes carried by the hood and the hanger, and a vertically-adjustable anode passing through said guide-boxes, substantially as and for the purposes described.

5. In an electrical furnace, the combination with an inclosed furnace-chamber and a suspension-beam, of a hanger depending from said beam and carrying an insulated guide box, a fume-collecting hood guided by the hanger and the suspension-beam, and provided with an insulated guide-box which is in vertical alinement with the guide-box of the hanger, and a vertically-adjustable anode fitted in the guide-boxes of the hood and the hanger, substantially as described.

6. In an electrical furnace, the combination with an inclosed fu rnace-chamber and a fume collecting hood, of a bearing-ring attached to the hood and provided with an insulated guide-box which is arranged therein to form the exit-openings for the fumes and gases arising from said retort, and an anode passing through said guide-box and insulated thereby from the bearing-ring and the hood, substantially as and for the purposes described.

7. In an electrical furnace, the combination with an inclosed furnace-chamber having a cathode, of a fixed overhead hanger, a vertically-adjustable fume-collecting hood provided with'guide-rods fitted to said hanger, the vertically-alined insulating guide-boxes carried by the hanger and said hood, and an anode movable in said guide-boxes, substantially as described.

, 8. In an electrical furnace, the combination with an inclosed furnace-chamber, of a revoluble carrier mounted thereon, a separate closure or head having a hinged connection with said carrier to rotate therewith and adapted to be adjusted independently of the carrier for exposing the furnace-chamber, and a stirrer or plow mounted on the closure or head and depending therefrom within the f urnace-chamber, substantially as and for the purposes described.

9. In an electrical furnace, the combination with an inclosed furnace-chamber, of a revoluble carrier mounted on said furnacechamber, a sectional closure havingits members hinged to the carrier to be sustained thereby over the furnace-chamber and adjustable independently of the carrier and of each other to expose the furnace-chamber, a

ranged to inclose said furnace-chamber, a

counterpoise for said fume-collecting hood, a I

vertically-movable anode guided in and insulated from said hood, an independent counterpoise connected to said anode, and electrical connections for the anode-carrier and the cathode, substantially as described.

In testimony that We claim the foregoing as our own We have hereto affixed our signatures in the presence of two Witnesses.

HILLIARY ELDRIDGE. DANIEL JOHNSON CLARK. SYLVAIN BLUM.

Witnesses:

E. R. OHEEsBoRoUGH, B. I. WILLOOXEN. 

